JOURNAL OF RESEARCH IN DENTAL SCIENCES
Year:2009 | Volume:5 | Issue:4|Papers Count:8

Background and aim: The previous studies have reported that the prognosis of multirooted teeth are poor because of the difficulty of narrow furcations debridement with current periodontal instruments. Purpose: The purpose of the present study was to document the buccal furcation entrance diameter of the mandibular molars in a sample of Iranian population.Materials & Methods: We chose 35 mandibular molar teeth. The buccal furcation entrance was marked by two periodontists with a grafit pencil and was accepted by 3 other periodontists, then they were scanned by the sony scanner and the buccal furcation entrance diameter was measured by photoshop and correll soft wares with 0.1 accuracy and 12.5% magnification. Each measurement was repeated twice by 2 different periodontists. Summary statistical measures (Mean, Standard deviation, Median, Mode and Confidence Interval) were calculated for the variable.For comparison of the measurements of the two examiners Paired Samples student T-test were used.The level of statistical significance was established at P<0.05.Results: The average width of the buccal furcation entrance in mandibular molars was measured 1.3 by the first examiner and 1.27 by the second examiner and the statistical difference was not significant (P=0.42).Conclusion: The results of the present study suggest that regardinfg the blade face width of the curettes and also ultrasonic tips, in this sample of teeth (chosen from the Iranian population) buccal furcations can be predictably debrided by both periodontal curettes and ultrasonic tips.

Background and aim: According to the importance of studentd anxiety at the time of examination and its effect their educational success and progress and also because of nonexistence of convincing reports in verified researches of regular genetic evaluation, this survey has been done with on ordinary method (the final evaluation) to examine the eddect of regular genetic evaluation on first grade students in high school in 1387 – 88.Material and methods: The survey was done through empirical method. All students of first grade in high school from two classes were examined. At first the extent of educational progress through a test and the extent of anxiety through the TAI standard questionnaires and the extent of creativity of students through Abedi creativity questionnaire were determined. Students of twoclasser were accidentally grouped into experimental and control group. A lesson according to its chapter was teached by a teacher and after every two sessions, the regular genetic evaluation has been done for experimental group. And at the end evaluation was done for two groups. Questions and days in which classes were held and also treating toward students in two classes were all the same. The effect of genetic evaluation method on 3 criterians of educational progress, test anxiety and creativity were examined and statistically judged with Menuvitny test.Conclusion: the number of students in control class is 32 and in experimental group are 31. The extent of primary educational progress, anxiety and creativity of students in 2 groups were the same. The extent of creativity in control group is 141/06±14/74 and in experimental group is 146/12±13/7 (P<0/2) and the extent of educational progress in control group at the end of survey is equal (13/43±3/56) standard deviation And in experimental group is 15/54±3/97 (P<0/03) and the extent of anxiety in control group is 47/03±13/98 mean and in experimental group is 41/29±7/79 standard deviation (P<0/05) It seems that regular genetic evaluation causes reduction in test anxiety and improvement in educational progress but it does not have any effect on learner’s creativity.

Background and aim: Considering wide spread plaque index and its side effects we must find a way to reduce and control dental plaque. Oral-B has claimed that one of its products named Pulsar toothbrush has better effects on controlling the plaque due to micro pulse movement of its bristles. This research was done among 12 year-old female students in a state and private school, in Tehran in 1386.Methods and Materials: This Cross Over experimental trial was performed on 24 people (48 samples).primary plaque index was measured by Turesky – Index and students were devided randomly in to two groups. The first group were given Classic toothbrushes and second group presented with Pulsar toothbrushes. We ask the students to use tooth brushes for 3 weeks. They did not recive any training about using tooth brushes.The plaque index measured at the end of the third week and after a 2- week Wash out, the groups were changed. We repeated the same process.Conclusion: Trial was done on 24 people. The primary and secondary plaque results in the group of Classic tooth brush was -0/25+0/43 which had been reduced by%17and in Pulsar group it was 0/1+0/55 which shows a%7/9 increase. The changes between groups were meaningful.Results: It seemed that despite Oral-B's claim Pulsar is not able to decrease dental plaque more than other types.We recommend a preliminary test-period before applying new products.

Background and aim: The third molar is the most common impacted tooth and several complication occure caused by impaction. One of these consists of pricoronitis. dontogenic cyct and tumor and jaw fracture.thus surgical extraction is the common method of treatment. two common surgical method employ the envelop flap and triangular flap. In consideration of the high incidence of impaction of third molar. this study evaluates the effectiveness these two flaps and their complication and post operative packet depth distal to the second molar.Material and method: A sequential randomized & controlled trial was done on 15 patients at our dental university. After obtaining concent the second molar was probed in six site and recorded.an envelop flap was reflected in one side and a triangular flap was reflected in the other side and the impaction was removed. After one to three months post surgery probing was done.Result: All the patients in the triangular flap group presented with greater pain and swelling than the other group one week post surgically.Four patients had pain which lasted up to one month. However no significant different were seen between two flap methods regarding probing depth after third molar surgery.Conclusion: Probing depth distal to the second after third molar surgery is not depended on flap design.

Background and aim: Microleakage at the margins of amalgam s has always been a problem caused due to different reasons. One of these reasons is incomplete fitness of amalgam restoration on the tooth which is related to the factor of bonding amalgam to the tooth. Therefore, the purpose of this study was to microleakage of amalgam restorations by using two bonding systems of All-Bond2 and Scotch Bond multi purpose plus.Materials and Methods: In this Invitro study, a number of 30 human premolar Teeth were selected and were divided in to 3 groups. Class V cavities were prepared in buccal surface. Scotch Bond multi purpose plus and All-Bond 2 were used in two groups of bonding systems. No bonding system was used in the third group. Tytine amalgam was inserted in the cavities and the samples were prepared for the evaluation of microleakage after thermocycling, use of Dye and sectioning. Dye penetration was evaluated under a stereomicroscope. Kruskal-wallis, Dunn test and Wilcoxan were also applied to evaluate differences between the occlusal and cervical Surfaces for each group. (a=0/05).Results: The obtained statistical results showed that leakage values in amalgam restorations was not significantly difference between two bonding systems (P> 0/05) And leakage values on gingival margins was significantly more than occlusal margins In each group (P< 0/05).Conclusion: Use of two bonding systems, All-Bond 2 and Scotch Bond multi- purpose plus in class V cavities were restorated with Spherical amalgam decrease leakage values significantly.

Background and aim Unawareness of tooth size in patients with hypodontia may lead to some clinical problem while treating these patients..Purpose: The aim of the present study was to find the relationship between hypodontia and tooth size in subjects with and without hypodontia in orthodontic department of dental college of Azad medical university between years 2007-2008.Material and Methods: A historical cohort study was designed to evaluate the size of the teeth in subjects suffering from hypodontia.80 subjects comprised of 40 female subjects with normal complete dentition as controls and 40 female subjects with missing at least two units congenitally were selected as study group.. The only differences were presence of all intact teeth in control group.. mesio distal width of the 11, 13, 14, 16 and 21, 23, 24, 26were measured to a nearest of 0.1 mm using a vernier caliper. Student T-Test was used to analyze the obtained data. Results: This study were carried out on 80 subjects include 40 female as control and 40 female as study group. The mean of Mesiodistal diameter of upper molar was 9.25±0.96 mm and 10±1.03 mm in study and Control groups respectively. Statistically a significant differences between two groups were observed (p< 0.001). In study group the average mesiodistal width of upper first premolars was 7.15±0.52 mm and in control group was 6.29±0.5 mm. The differences between two groups was statistically significant (p< 0.001).In study group mesiodistal width of 11, 21, 13, 23 were significantly smaller than control group (P< 0.001).Conclusion: Mesiodistal diameter of the upper teeth in female patients with hypodontia is smaller than female subjects without hypodontia.

Background and aim: Correct and ontime diagnosis of soft tissue lesions of oral carity provide the possibillity of controlling and proper managing for patient and prevent lesion from reaching more advanced stages. The main purpose of this resesrch is planning and evaluating of a decision support system software in order to diagnose the soft tissue lesions of oral cavity.Material and Methods: In designing of software system the information related to lesions base of famous books and references collected and algorythms related to each set of lesions designed. then these algorythms entered to the decision support system soft ware. Gold Standard for evaluating of software system efficiency are different pictures of soft tissue lesions of various atlas of oral medicine, hence we choiced 61 specimen of these lesions with patient’s history, clinical features and other necessory information, for evaluating of the soft ware system, efficiency.Then, with regarding to these mentioned in formation about every lesion, three observers including 3 sepecialist in oral medicine, 30 general dentist, and 30 end term student of dentistry provide their diagnosis first without and second with software system.Results: The number of specimen that have been diagnosed correctly by observer 1, without using software system were (61specimen) and with using soft ware system were (61 specimen).The number of specimen that have been diagnosed correctly by observer 2, without using software system were (20 specimen) and with using soft ware system were (43 specimen). The number of specimen that have been diagnosed correctly by observer 3, without using software system were (36 specimen) and with using soft ware system were (50specimen).Conclusion: Using algorythms and designed system are useful and reliable for diagnose and provide useful treatment plan of soft tissue lesions of oral cavity.

Background and aim: The aim of this study was to evaluate the prevalence and some of its possible risk factors on causing oral cleft in Imam Khomani Hospital. The study was a 7 year cross sectional study from March 1998 to March 2005.Methods and Material: This study was done under the condition of existing data.25 live births with cleft lip and /or palate [CL+P] were born between 20th of March 1998 and 20th of March 2005 from the total of 11651 live births in Imam Khomani hospital. After recognizing the child as a cleft patient, previous and following children born were recognized as a non cleft sample. Cleft and non cleft samples were analyzed by gender, mother’s age, parity, close relative marriage and infant’s weight and then compared with chi-square.Results: The overall incidence was 2.14 per 1000 live births. CL+P was more prevalent which was 52% and the least incidence was for “only cleft lip” patients, which was 12%.Conclusions: This study reveals that the incidence of oral clefts in Tehran is higher than many other countries. Close relative marriage and low birth weight in cleft group were significantly different from those of non cleft group.